SELECT sla.incident_generated_sla from eventedge_events_sla sla
where e.client_id=sla.client_id and sla.priority_id=e.priority_id
(SELECT sla.incident_generated_sla from eventedge_events_sla sla
where e.client_id=sla.client_id and sla.priority_id=(IsNull(e.priority_id,"2")))
你已经几乎做到了。
检查这修正自己的尝试:
SELECT sla.incident_generated_sla from eventedge_events_sla sla
where e.client_id=sla.client_id and sla.priority_id=ISNULL(e.priority_id,2)
现在,我不知道你的“E”是什么,但如果这是你要找的CLIENT_ID宣布,它应该工作。
仔细看看我对ISNULL的更正。
编辑:在评论这个答案是正确的;
SELECT
e.event_start_time,
sla.incident_generated_sla
FROM
eventedge_events_sla sla
left outer join eventedge_events e
ON e.client_id = sla.client_id
AND isnull(e.priority_id,2) = sla.priority_id
标记您正在使用的DBMS(MySQL,MS SQL Server等)。 –
'COALESCE'? https://dev.mysql.com/doc/refman/5.7/en/comparison-operators.html#function_coalesce –